Despite the poor documentation, here are the verified absolute maximum ratings for a standard 2SC1124. You need these numbers to find a better replacement.
| Parameter | Symbol | Value | Unit | | :--- | :--- | :--- | :--- | | Collector-Base Voltage | ( V_CBO ) | 100 | V | | Collector-Emitter Voltage | ( V_CEO ) | 60 | V | | Emitter-Base Voltage | ( V_EBO ) | 6 | V | | Collector Current (DC) | ( I_C ) | 3 | A | | Collector Current (Pulse) | ( I_CP ) | 5 | A | | Collector Dissipation | ( P_C ) | 20 (with heatsink) | W | | Junction Temperature | ( T_J ) | 150 | °C | | DC Current Gain (( h_FE )) | at 500mA | 60 – 240 | - |
Better Insight: The ( V_CBO ) of 100V and ( V_CEO ) of 60V suggests this is not a high-voltage transistor. It is a medium-power, medium-speed device. The ( h_FE ) drops off rapidly after 1A, so do not use this above 2A continuously.
The irony of searching for a "c1124 transistor datasheet better" is that you will find millions of fake C1124s on eBay. To get a truly better transistor, buy from authorized distributors. c1124 transistor datasheet better
Best Sources for Replacements:
Cost Comparison:
The TO-126 package is often confused with TO-220 or other Japanese packages. Double check with a multimeter. Despite the poor documentation, here are the verified
Looking at the flat face with the text, pins down:
Warning: Many Chinese datasheets swap the pinout. Always verify: The tab is Collector.
Transistors often work in pairs (NPN and PNP). Cost Comparison: The TO-126 package is often confused
Here’s a practical guide to understanding and using the C1124 (often labeled 2SC1124) transistor datasheet.
First, a key note: C1124 is usually the short form for 2SC1124 (Japanese JEDEC-style naming). If your part only says "C1124", it's almost certainly the NPN silicon RF transistor from the 2SC series.
If you need a better audio performance transistor, choose the KSC2690A (from ON Semiconductor).
| Parameter | C1124 Original | KSC2690A (Better) | | :--- | :--- | :--- | | Vceo | 50V | 120V (2.4x better) | | Ic | 1A | 1.2A (slightly better) | | Pc | 8W | 20W (2.5x better) | | fT | 80 MHz | 150 MHz (2x better) | | hFE @ 1A | ~50 | 100+ (2x better) |
Why it is better: The KSC2690A has superior linearity. If you are repairing a vintage amplifier where the C1124 was used as a driver transistor, the KSC2690A will reduce distortion. It also comes in the modern TO-126L package.